Powder Coat Finish on Patio Furniture Looks Dull

I have a set of black metal mesh patio furniture that's about 8 years old. The powder coat finish is beginning to lose its luster and take on a lighter, faded look. I've washed it and that didn't help. Is there something I can apply to return it to its darker color? It almost looks as if oiling it with something might help, but I'm a little wary of trying that in case it would end up in a gunky mess.

We had the same problem but with white metal patio furniture. Tried sanding it and painting it with a brush - too messy and did not look good. We finally just lightly sanded it down and spray painted it white again. I still hate the set but it looks great :-)

Here in the UK we have a paint called Hammerite. It's made specially to use on metal. It comes in smooth or "hammered' finishes If you can get in the States it would be ideal for your patio furniture. Hope this helps.